Photographic elements generally comprise hydrophilic binders, e.g. gelatin as vehicles for the imaging chemistry and in the protective overcoat. These hydrophilic colloids can absorb moisture and become tacky in humid environments and at elevated temperatures causing the photographic materials to stick to each other, for example, if packed in a stack. To eliminate these difficulties, it is conventional to incorporate finely powdered grains or matting agents (beads) into the protective layer to increase the surface roughness and prevent contact and subsequent sticking. It is desirable that these matte beads are non-hydrophilic and consequently they are comprised of materials different from the binders. Because of the different composition, these matte beads may have different refractive index. When light is passed through the photographic element, such as in photographic printing or projection, both the increased surface roughness and difference in refractive index can cause a non-uniform light path and result in graininess in photographic prints or mottle in projected images. For this reason, manufactures have been using a large amount of non-process surviving (soluble) mattes, designed to solubilize in high pH solutions, in combination with a small amount of process surviving (permanent) matte.
In recent years, the conditions under which the photographic materials are utilized have become more severe. For example, conventional photographic materials are designed for storage and housing after processing in a plastic pouch or envelope where the processed photographic materials do not come into direct contact. In recent years, there is an increase in demand for photographic materials to be returned post process in the cartridge for storage and future interface needs. The photographic materials come into direct contact during these post process windings, unwinding, rewinding, and handling. This requires the use of an increased level of processing surviving mattes for reducing self-adhesion. However, it has also caused an increase in matte cinch scratches and abrasion marks on the photographic materials which may become visible on projection or subsequent printing.
Recently, significant advancements have been made with regard to the methods of preparing photographic material. For example, the speed of coating, finishing, cutting, and processing has been increased. These improvements have also resulted in a significant increase in the amount of scratches and abrasion marks on the side opposite to that containing matte particles.
Therefore the present invention is directed to the objective of providing improved topmost protective layers which allow photographic elements to be used in humid environments and at elevated temperatures with good ferrotyping performance both before and after processing, and which also provide photographic elements with excellent resistance to matte cinch scratch and abrasion in manufacture and use.